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Fil: Varone, Laura. Fundacion para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas; Argentina

The feeding responses of the predatory stink bugs, Euthyrhynchus floridanus (L.) and Podisus maculiventris Say (Hemiptera: Pentatomidae), to the kudzu bug Megacopta cribraria (Fabricius) (Hemiptera: Plataspidae) were studied in the laboratory. Before the experiments, E. floridanus and P. maculiventris males, females and third-fourth instars were kept individually in Petri dish with a bean pod and moistened paper for 24 h. Then, they were exposed to a single male, female or third instar M. cribraria with and without Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae) as alternative prey for 24 h. Another laboratory experiment was conducted to estimate the predation rate at different prey densities. A single predator male or female was exposed to different M. cribraria adult densities (1 to 5). Euthyrhynchus floridanus was 20-40% more efficient than P. maculiventris at feeding on M. cribraria adults in the laboratory with or without C. includes as alternative prey. The prey preference of both predators were not affected by the presence of C. includes, and all the predator stages preferred to feed on M. cribraria over C. includens. Both predators killed increasingly greater number of preys when exposed to increasing prey densities until a certain limit was reached. The limit in number of prey killed was probably imposed by predator satiation in conjunction with prey defense mechanisms. This study demonstrated that E. floridanus is a potential biocontrol agent for M. cribraria. However, more testing is necessary to determine the impact of this predator in the field. ResumenLas repuestas alimenticias de las chinches hediondas depredadoras, Euthyrhynchus floridanus (L.) y Podisus maculiventris Say (Hemiptera: Pentatomidae) a la chinche del kudzu Megacopta cribraria (Fabricius) (Hemiptera: Plataspidae) fueron estudiadas en laboratorio. Antes de los experimentos, los machos, hembras y ninfas del 3ro-4to estadios de E. floridanus y P. maculiventris fueron mantenidos individualmente in cajas de Petri con una vaina de frijol y papel humedecido durante 24 h. Luego, fueron expuestos a un macho, hembra o tercer ninfal instar del M. cribraria con y sin Chrysodeixis includens (Walker) (Lepidoptera: Noctuidae) como presa alternativa durante 24 h. Otro experimento de laboratorio fue llevado a cabo para estimar la tasa de predacion a diferentes densidades de presa. Un depredador individual macho o hembra fue expuesto a diferentes densidades de M. cribraria adultos (1 a 5). Euthyrhynchus floridanus fue un 20-40% mas eficiente que P. maculiventris alimentandose de M. cribraria adultos con o sin C. includens como presa alternativa. La preferencia de presa de ambos depredadores no se vio afectada por la presencia de C. includens. Ambos depredadores consumieron un mayor numero de presas cuando fueron expuestos a un aumento en el numero de presas hasta que cierto limite fue alcanzado. El limite en el numero de presas consumidas estuvo condicionado cuando el depredador estuvo saciado combinado con los mecanismos de defensa de la presa. Este estudio demostro que E. floridanus tiene potencial como agente de control biologico de M. cribraria. Sin embargo, se hacen necesario mas pruebas para determinar el impacto de este depredador en el campo. View this article in BioOne

Apanteles opuntiarum Martínez & Berta (Hymenoptera: Braconidae) is a native natural enemy of the cactus moth, Cactoblastis cactorum Berg (Lepidoptera: Pyralidae) in Argentina, where the 2 species are believed to have co-evolved. Cactoblastis cactorum is an established invasive pest in the US that is rapidly spreading throughout the southeast. Apanteles opuntiarum was imported from Argentina, and reared at the Division of Plant Industry containment facility in Gainesville, Florida, for study as a possible biocontrol agent for release in the US to control C. cactorum. A DNA barcode was developed to enable the identification of the reared parasitoid population. The mitochondrial cytochrome oxidase I (COI) gene of the A. opuntiarum reared in Florida containment was found to be identical to its Argentine founders, but distinctly different from the COI sequences of all other reported Apanteles species in the NCBI (National Center for Biotechnology Information) GenBank. Additionally, the AoF1 and AoR1 primer pair developed in this study specifically amplified the COI gene of A. opuntiarum, but did not amplify the COI gene of the host C. cactorum. Therefore, the COI gene fragment identified in this study has the potential to be used as a DNA barcode specific to A. opuntiarum that can aid in tracking and identifying this parasitoid inside hosts. Apanteles opuntiarum Martínez & Berta (Hymenoptera: Braconidae) es un enemigo natural de la polilla de la tuna Cactoblastis cactorum Berg (Lepidoptera: Pyralidae) en Argentina, su rango nativo, donde han co-evolucionado. Cactoblastis cactorum es una especie invasora establecida en Estados Unidos, que se está dispersando rápidamente hacia el sudeste de este país. Apanteles opuntiarum fue importado desde Argentina y es criado en la cuarentena de Gainesville, Florida (Division of Plant Industry), donde está siendo evaluado como posible agente de control de C. cactorum, para ser liberado en Estados Unidos. Se desarrolló un código de barras de ADN para permitir la identificación de la población de parasitoides criada. Se encontró que el gen de la citocromo oxidasa mitocondrial I (COI) de los A. opuntiarum criados en Florida fue idéntico al de sus fundadores argentinos, y claramente diferente de las secuencias de COI de todas las demás especies de Apanteles reportados en el GenBank del NCBI (Centro Nacional de información sobre biotecnología). Además, el par “primer” AoF1 y AoR1 desarrollado en este estudio amplificó específicamente el gen COI de A. opuntiarum, y no amplificó el gen de la COI del hospedador C. cactorum. Por lo tanto, el fragmento del gen COI identificado en este estudio tiene el potencial para ser utilizados como un código de barras de ADN específico para A. opuntiarum que puede ayudar en el seguimiento y la identificación de este parasitoide dentro de los hospedadores Fil: Srivastava, Mrittunjai. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Srivastava, Pratibha. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Karan, Ratna. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Jeyaprakash, Ayyamperumal. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Whilby, Leroy. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Rohrig, Eric. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Howe, Amy C.. Florida Department of Agriculture and Consumer Services; Estados Unidos Fil: Hight, Stephen D.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos Fil: Varone, Laura. Fundación para el Estudio de Especies Invasivas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

A push-pull strategy for reducing populations of the thrips Frankliniella occidentalis (Pergande), F. bispinosa (Morgan) and F. tritici (Fitch) in tomato was evaluated. Push components consisted of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component consisted of the companion plant Bidens alba (L.). Replicated field experiments were conducted in 2011 and 2012. Adult and larval thrips were reduced by UV-reflective mulch during early and mid-flowering of tomato. Spray applications of kaolin were effective in reducing adult and larval thrips during early, mid- and late-flowering. The pull effects of the B. alba companion plants were additive and sometimes interactive with the push effects of UV-reflective mulch and kaolin in reducing the adult males of each thrips species and the females of F. bispinosa. The strategy was not effective in reducing the adult females of F. tritici and F. occidentalis. In addition to attracting the Frankliniella species adults, the companion plants were hosts for the thrips predator Orius insidiosus (Say). The companion plants combined with UV-reflective mulch and kaolin proved effective as a push-pull system for suppressing flower thrips, including F. occidentalis which is a serious pest of tomato worldwide.

During our study on egg parasitoids of the kudzu bug in Florida, we collected egg masses of Megacopta cribraria on kudzu and catnip for laboratory rearing. We found a new egg parasitoid, Ooencyrtus nezarae on M. cribraria, which represents the first Florida record of this parasitoid species. The wasp is widely distributed in Asia, and it will strengthen biological control of the kudzu bug in Florida. Future studies will assess comparative parasitism levels of Paratelenomus saccharalis and O. nezarae, as well as the dynamics of populations of these biological control agents.

The spread of the western flower thrips, Frankliniella occidentalis (Pergande), has resulted in the world-wide destabilization of established integrated pest management programs for many crops. It is hypothesized that frequent exposure to insecticides in intensive agriculture selected for resistant populations, which allowed invasive populations in the eastern USA to overcome biotic resistance from the native community of species. Research conducted in Florida to understand the role of biotic factors in limiting the abundance of the western flower thrips is reviewed. Orius spp. (Hemiptera: Anthocoridae) are effective predators that suppress populations of thrips on crop and non-crop hosts in southern and northern Florida. Orius are more effective predators of the western flower thrips than the native flower thrips, F. tritici (Fitch) and F. bispinosa (Morgan). The native species are competitors of the western flower thrips. Excessive fertilization and the use of broad-spectrum insecticides in crop fields further enhances populations of the western flower thrips. Interactions with native species clearly limit the abundance of western flower thrips in Florida, but populations are abundant in fertilized crop fields where application of insecticides excludes predators and competitor species.

Newer, selective insecticides with few negative impacts on natural enemies and competitor species are needed for effective, sustainable management of the western flower thrips, Frankliniella occidentalis (Pergande). The purpose of this study was to evaluate the impacts on natural enemies and competitor thrips species of insecticides used for control of western flower thrips in fruiting vegetables. Trials with tomato (Solanum lycopersicum L.) and with pepper (Capsicum annuum L.) were conducted to evaluate insecticide treatment effects on western flower thrips and natural enemies at the North Florida in 2008, 2009, 2010 and 2011. A number of insecticides from different classes showed moderate to high efficacy against western flower thrips. The broad-spectrum insecticides acetamiprid, methomyl, and tolfenpyrad demonstrated activity against the pest, while also reducing populations of the key predator of thrips in pepper, Orius insidiosus (Say) (Hemiptera: Anthocoridae). Insecticides that showed litt...

The cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), is an invasive species in North America, where it poses a threat to species of Opuntia Mill. of economic and ecological importance. The parasitoid Apanteles opuntiarum Martinez & Berta (Hymenoptera: Braconidae) is currently under evaluation as a potential biological control agent. This study was conducted to develop a parasitoid rearing protocol, with special attention to laboratory sex ratio and the effects of inbreeding. The parasitoid rearing method used a natural cactus host diet for culture of the moths. Female wasps were mated with siblings, non-siblings, or a combination. Clutch size, clutch number, and offspring sex ratios were recorded. The effects of sibling mating on these factors were analyzed. Offspring of sibling-mated parasitoids exhibited a significant increase in female sex ratio. The rearing method produced 6 successive generations in captivity with no additional introductions of genetic material. Hence, the protocol appears suitable for long-term maintenance of quarantine colonies. The effects of inbreeding suggest that natural populations of A. opuntiarum are subject to local mate competition. Therefore, some amount of inbreeding is recommended for maintenance of an optimal sex ratio of A. opuntiarum in laboratory colonies.

Botryosphaeria spp. are ligninolytic ascomyceteous fungi that incite many diseases in economically important woody plant species. Four Botryosphaeria isolates, Botryosphaeria rhodina (Lasiodiplodia theobromae), Botryosphaeria obtusa, Botryosphaeria dothidea and Botryosphaeria ribis (Neofusicoccum ribis) were used in this study. Ten naturally occurring phenolic compounds from plants were tested to evaluate their effect on mycelium growth and the production of ligninolytic and pectinolytic enzymes. The effect of phenolic compounds in vitro varied with the Botryosphaeria isolates. Inhibition of mycelium growth was dose-dependent, and varied from 2 to 100% inhibition in the ten phenolic compounds tested except syringic acid, which has no toxic effect on mycelium of Botryosphaeria isolates. A significant decrease in laccase production occurred when Botryosphaeria isolates were grown on phenolic compounds. Benzoic acid significantly inhibited pectinase activity in all isolates. The percent inhibition of pectinase activity in B. dothidea and B. obtusa was significantly increased in the presence of salicylic acid and syringic acid, respectively.

Characteristics of accumulation and tolerance of cadmium (Cd) in Bidens tripartite L were investigated to identify Cd-accumulating properties. In this study, pot culture experiment and site sampling experiments were conducted to assess whether this plant is a heavy metal hyperaccumulator or accumulator. The results indicated that the Cd enrichment factor (concentration in plant/soil) and Cd translocation factor (concentration in shoot/root) of B. tripartite was principally > 1 in pot culture and concentration gradient experiments. Shoot biomass was not reduced significantly (p < 0.05) compared to the controls. However, the Cd concentration in B. tripartite shoots was not higher than 100 mg kg(-1), the threshold concentration for a Cd-hyperaccumulator. In the site sampling experiment, B. tripartite also showed Cd-accumulator properties. Based on these results, B. tripartite could be identified as a Cd-accumulator. Thus, B. tripartite should only be considered as a Cd-accumulator. (C) 2009 Elsevier B.V. All rights reserved.

Solarium nigrum is a newly found Cd-hyperaccumulator which showed very high remediation efficiency in polluted soil. Seed germination experiments with different illumination and seed-soaking reagents were conducted in constant temperature box and greenhouse with soil as burgeon base. The results showed that the germination rate with alternating light/dark photoperiod was about twice of that without fighting (p l 0.05), suggesting that illumination is one of the important conditions for seed germination of S. nigrum. All treatments with seed-soaking reagents significantly increased the seed germination rate of S. nigrum (p l 0.05). Treatment with H2O2 (0.1%) had the shortest germination time. The germination rate of seeds that were not washed in water following soaking was 2-3 times higher than that of seeds that were washed after soaking. (C) 2009 Elsevier B.V. All rights reserved.

The effects of timing in phosphate application on plant growth and arsenic removal by arsenic hyperaccumulator Pteris vittata L. of different ages were evaluated. The hydroponic experiment consisted of three plant ages (A 45d , A 90d and A 180d ) and three P feeding regimens (P 200+0 , P 134+66 and P 66+134 ) growing for 45 d in 0.2-strength Hoagland–Arnon solution containing 145 μg L −1 As. While all plants received 200 μM P, P was added in two phases: during acclimation and after arsenic exposure. High initial P-supply (P 200+0 ) favored frond biomass production and plant P uptake, while split-P application (P 134+66 and P 66+134 ) favored plant root production. Single P addition favored arsenic accumulation in the roots while split-P addition increased frond arsenic accumulation. Young ferns (A 45d ) in treatment P 134+66 were the most efficient in arsenic removal, reducing arsenic concentration to below 10 μg L −1 in 35 d. The results indicated that the use of young ferns, coupled with feeding of low initial P or split-P application, increased the efficiency of arsenic removal by P. vittata .

Summary • Brake fern, Pteris vittata , not only tolerates arsenic but also hyperaccumulates it in the frond. The hypothesis that arsenic hyperaccumulation in this fern could function as a defense against insect herbivory was tested. •F ronds from control and arsenic-treated ferns were presented to nymphs of the grasshopper Schistocerca americana . Feeding damage was recorded by visual observation and quantification of the fresh weight of frond left uneaten and number of fecal pellets produced over a 2-d period. Grasshopper weight was determined before and after 5 d of feeding. • Grasshoppers consumed significantly greater amounts of the frond tissue, produced more fecal pellets and had increased body weight on control plants compared with grasshoppers fed arsenic-treated ferns. Very little or none of the arsenic-treated ferns were consumed indicating feeding deterrence. In a feeding deterrent experiment with lettuce, sodium arsenite at 1.0 m M deterred grasshoppers from feeding whereas 0.1 m M did not. In a choice experiment, grasshoppers preferred to feed on lettuce dipped in water compared with lettuce dipped in 1.0 m M sodium arsenite. • Our results show that arsenic hyperaccumulation in brake fern is an elemental defense against grasshopper herbivory.

The spread of the western flower thrips, Frankliniella occidentalis (Pergande), has resulted in the world-wide destabilization of established integrated pest management programs for many crops. It is hypothesized that frequent exposure to insecticides in intensive agriculture selected for resistant populations, which allowed invasive populations in the eastern USA to overcome biotic resistance from the native community of species. Research conducted in Florida to understand the role of biotic factors in limiting the abundance of the western flower thrips is reviewed. Orius spp. (Hemiptera: Anthocoridae) are effective predators that suppress populations of thrips on crop and non-crop hosts in southern and northern Florida. Orius are more effective predators of the western flower thrips than the native flower thrips, F. tritici (Fitch) and F. bispinosa (Morgan). The native species are competitors of the western flower thrips. Excessive fertilization and the use of broad-spectrum insecticides in crop fields further enhances populations of the western flower thrips. Interactions with native species clearly limit the abundance of western flower thrips in Florida, but populations are abundant in fertilized crop fields where application of insecticides excludes predators and competitor species.

Crapemyrtle is a common landscape planting that is a resource subsidy for beneficial insects. Field studies were conducted to determine the influence of crapemyrtle flower color on the population abundances and predator-prey dynamics of the herbivorous Frankliniella species and the predator Orius insidiosus. Adults and immatures of predator and prey were highly anthophilous, preferring white 'Acoma' flowers compared with lavender 'Apalachee', red 'Carolina Beauty', and pink 'Choctaw'. The predator was aggregated with its prey in a density-dependent manner: the adults by preferring the crapemyrtle clones also preferred by the thrips and the nymphs by direct tracking or as a function of increased prey and fecundity. Acoma was best for preference and buildup of O. insidiosus populations, and it was the only clone where there was no buildup in thrips populations. Two species of Karnyothrips (Thysanoptera: Phlaoethripidae), predators of small insects, were common in Tillandsia usneoides, an epiphyte on the crapemyrtle. Crapemyrtle is a bridge to enhance populations of O. insidiosus during summer months when there are few other hosts in the southern USA.

Arsenic hyperaccumulator Pteris vittata L. (Chinese brake fern) grows well in arsenic-contaminated media, with an extraordinary ability to tolerate high levels of arsenic. An expression cloning strategy was employed to identify cDNAs for the genes involved in arsenic resistance in P. vittata. Excised plasmids from the cDNA library of P. vittata fronds were introduced into Escherichia coli XL-1 Blue and plated on medium containing 4 mM of arsenate, a common form of arsenic in the environment. The deduced amino acid sequence of an arsenate-resistant clone, PV4-8, had cDNA highly homologous to plant cytosolic triosephosphate isomerases (cTPI). Cell-free extracts of PV4-8 had 3-fold higher level of triosephosphate isomerase (TPI) specific activities than that found in E. coli XL-1 Blue and had a 42 kD fusion protein immunoreactive to polyclonal antibodies raised against recombinant Solanum chacoense cTPI. The PV4-8 cDNA complemented a TPI-deficient E. coli mutant. PV4-8 expression improved arsenate resistance in E. coli WC3110, a strain deficient in arsenate reductase but not in AW3110 deficient for the whole ars operon. This is consistent with the hypothesis that PV4-8 TPI increased arsenate resistance in E. coli by directly or indirectly functioning as an arsenate reductase. When E. coli tpi gene was expressed in the same vector, bacterial arsenate resistance was not altered, indicating that arsenate tolerance was specific to P. vittata TPI. Paradoxically, P. vittata TPI activity was not more resistant to inhibition by arsenate in vitro than its bacterial counterpart suggesting that arsenate resistance of conventional TPI reaction was not the basis for the cellular arsenate resistance. P. vittata TPI activity was inhibited by incubation with reduced glutathione while bacterial TPI was unaffected. Consistent with cTPI's role in arsenate reduction, bacterial cells expressing fern TPI had significantly greater per cent of cellular arsenic as arsenite compared to cells expressing E. coli TPI. Excised frond tissue infiltrated with arsenate reduced arsenate significantly more under light than dark. This research highlights a novel role for P. vittata cTPI in arsenate reduction.

This study examined the metabolic adaptations of Pteris vittata L, an arsenic hyperaccumulator, under arsenic stress as compared to Pteris ensiformis, a non-arsenic hyperaccumulator. Both plants were grown hydroponically in 20% Hoagland medium in controlled conditions and were treated with 0, 133 or 267 μM arsenic as sodium arsenate for 1, 5 or 10 d. The fern fronds were analysed for differences in oxidative stress and antioxidant capacities after arsenic exposure. Upon exposure to 133 μM arsenic, concentrations of chlorophyll, protein and carotenoids increased in P. vittata whereas they decreased in P. ensiformis. The H2O2 and TBARs concentrations were greater in P. ensiformis than P. vittata in all treatments, indicating greater production of reactive oxygen species (ROS) by P. ensiformis. The levels of ascorbate and glutathione, and their reduced/oxidized ratios in the fronds of P. vittata of the control was much greater than P. ensiformis indicating that P. vittata has an inherently greater antioxidant potential than P. ensiformis. The lower levels of antioxidant compounds (ascorbate, carotenoids and glutathione) in P. ensiformis than P. vittata are consistent with its greater exposure to ROS and lower scavenging ability. The results together indicate that protection from oxidative damage by a greater level of ascorbate–glutathione pool is involved in the arsenic-tolerance in arsenic-hyperaccumulator P. vittata.

A biologically based integrated pest managefor pepper by Funderburk et al. (2000) and Reitz et ment program is fundamental in preventing al. (2003). Experimental design was a randomized the development of insecticide resistance, recomplete block, with 4 replications. Plot size was 1 surgence of populations of western flower thrips, raised, plastic mulched bed 9 m long on which there Frankliniella occidentalis (Pergande) (Thysanopwere 2 linear rows of pepper with a 13.8-cm plant tera: Thripidae), and replacement with nontarget spacing between and within rows for a total of 48 pest damage (Demirozer et al. 2012). The conservaplants per plot. Beds were irrigated with a single tion biological control component of the integrated trickle tube with emitters spaced every 30 cm at a pest management program is the most effective rate of 20,000 Ivha/day. Dates and rates of insecti way to manage thrips in pepper (Capsicum spp.; cide applications and of insect sampling are includ Solanales: Solanaceae) (Reitz et al. 2003). Species ed in Table 1. Foliar insecticides were applied with a of Anthocoridae are the most important worldwide C02-powered backpack sprayer equipped with 4 D7 predators of thrips. Within this family are minute nozzles with the amount of spray 430 L/ha. Drench pirate bugs with 2 species in Florida, Orius insidiotreatments were applied in a water solution of 200 sus (Say) and O. pumilio (Champion) (Hemiptera: mL/plant. Trickle tube treatments were applied in Anthocoridae). The minute pirate bugs are a valua water solution of 5.7 L/plot with a C02-powered able tool for controlling thrips as they prey preferinjector pressurized to 103 kPa, followed by 8 L of entially on the adults of the western flower thrips clean water rinse. Inline connectors with shut-off over the adults of the non-damaging native thrips valves were used to isolate the plots. Ten flowers species, F. tritici (Fitch) and F. bispinosa (Morgan) per plot (whenever possible) were collected on each (Baez et al. 2004). The damaging thrips larvae also of 6 sample dates and preserved in 70% alcohol with are preferred prey (Baez et al. 2004). About 1 minthe number of thrips and O. insidiosus determined ute pirate bug for every 180 thrips is sufficient for using 7 to 100 X magnification. The data for each suppression of the populations of thrips, and at a sample was converted to number per flower, pooled ratio of about 1 predator to 40 thrips, thrips populaover date, and transformed to log (x + 0.5) for anal tions are controlled (Funderburk et al. 2000). Natuysis of variance. When the overall treatment effect ral populations of minute pirate bug adults rapidly was significant at the P = 0.05 level, orthogonal invade pepper fields in sufficient numbers to control comparisons were used to separate treatment dif western flower thrips adults and larvae, but they ferences. Untransformed means per 10 flowers are must be conserved with judicious insecticide use reported in Table 1. (Funderburk et al. 2000, Demirozer et al. 2012). The adults of F. occidentalis and F. tritici ac An integrated pest management program for counted for 6 and 19% of the total thrips in the rm peppers that encompasses the simultaneous mantreated controls and there were no significant treat agement of multiple pests is being developed and ment differences (data not shown). The numbers of implemented (Demirozer et al. 2012). Ta further thrips were well below the economic thresholds es enhance the effectiveness of the conservation biotablished by Demirozer et al. (2012), with the ratio logical control component of this program, updated of predators in relation to prey sufficient in the cm information on insecticides labeled for fruiting vegtreated plots to result in thrips suppression. There etables against thrips or other pests that have little were treatment differences in the number of F. impact on populations of minute pirate bugs was bispinosa females, thrips larvae, and O. insidiosus reported (Funderburk et al. 2011). In the present nymphs (Table 1). When compared to the untreat report, imidacloprid 4.6SC (Bayer Crop Protection, ed control, 2 applications of cyantraniliprole 20SC Research Triangle Park, North Carolina) and cyanin the trickle tube did not reduce the numbers of traniliprole 10SE and 20SC (DuPont Crop Protecthrips or O. insidiosus in the flowers. However, the tion, Newark, Delaware) were evaluated against 2 applications of cyantraniliprole 20SC combined populations of thrips and minute pirate bugs, with a transplant treatment of imidacloprid 4.6SC Spinetoram SC (Dow AgroSciences, Indianapolis, resulted in 94, 82, and 88% reductions in numbers Indiana) was included as a standard foliar treatof F. bispinosa adults, thrips larvae, and O. insid ment. iosus nymphs, respectively. Unless there are unex Experimental procedures to evaluate the treatpected synergistic effects, this result showed that ment effects on adult and immature O. insidiosus the residual effect of a transplant application of and flower thrips were similar to those established imidacloprid lasted through pepper flowering and

The gametophyte development of Lomagramma sorbifolia (Willd.) Ching has been studied. Spore germination is of the polar and Vittaria-type. Prothallial development is either of the Adiantum-type, or more rarely of the Drynaria-type. This Adiantum-type is unusual among most of the other genera of the lomariopsidoid ferns. The Drynaria-type of gametophyte development is more characteristic of the lomariopsidoid ferns. Older prothalli are cordate and naked throughout. Early development seems to be somewhat plastic and perhaps of limited usefulness as a character for systematic purposes.

In the present study an attempt has been made to correlate the different soil factors with the growth of four different species of Isoetes L. Soil collected from natural habitats of Isoetes have been analysed for colour, texture, pH and available plant nutrients. The present analysis revealed that the habit of the plant of different species is influenced by edaphic diversity. It has also been found that the genus Isoetes is one of the most edaphically diversified genera of the pteridophyta. There was certain sensitivity of plant length in relation to the various soil factors. The lower scale of acidity favored the growth of Isoetes. The length of the plant decreases with the altitude. The nutrients like, zinc, manganese, iron and copper present in the soil showed significant relationships with the growth of the plants.

Phytoremediation is a cost-effective, simple and sustainable beneficiary technique to purify the polluted environment. Solanum nigrum L., a newly found cadmium (Cd) hyperaccumulator, has shown the potential to remediate Cd-contaminated soils. Present study investigated the effects of fertilizer amendments on the Cd uptake by S. nigrum. Chicken manure and urea are usual agricultural fertilizers and more environmental friendly. The results showed that Cd concentrations in shoots of S. nigrum were significantly decreased (p < 0.05) by 28.2–34.6%, as compared to that of without the addition of chicken manure, but not the case for urea treatment. However, Cd extraction capacities (g pot −1 ) in shoot biomass of S. nigrum were significantly increased (p < 0.05) due to increased shoot biomass. In addition, available Cd concentration in soil significantly decreased due to addition of chicken manure. Thus, urea might be a better fertilizer for strengthening phytoextraction rate of S. nigrum to Cd, and chicken manure may be a better fertilizer for phytostabilization. © 2009 Elsevier B.V. All rights reserved.

This study evaluated the ability and mechanisms of 19 Pteris and non-Pteris species to accumulate arsenic (As) in a hydroponic system spiked with 300 microM As. The study included four Pteris vittata accessions (China, India, Poland, and the United Kingdom), P. biaurita and 17 non-Pteris species. Among the accessions, P. vittata from China and UK were the most and the least efficient in terms of As accumulation. The non-Pteris species Chielanthes sinuta, Adiantum raddianum, Polystichum acrostichoides, Actiniopteris radiata, Pellaea rotundifolia, and Nephrolepis cordifolia concentrated As as effectively as the least efficient P. vittata ascension. As (III) in the fronds of P. vittata accessions ranged from 59% to 89% and for non-Pteris species it ranged from 47% to 65%. Maximum As accumulation coincided with highest percentage of As (III) in the fronds. The phosphorus (P) uptake of P. vittata accessions was 12-15 and 6-12 times greater than the As-uptake in the roots and fronds, respectively. In contrast, the P-uptake of non-Pteris species ranged from 9 to 151 and from 4 to 162 times the As-uptake, in the roots and fronds, respectively. Arsenic accumulation occurs at the expense of root and frond P-uptake. Root P-reduction is lower than frond and the P:As in the plant acquisition part (roots) is 1-3 times greater than that in accumulation part (fronds). A. radiata, C. sinuta, and P. acrostichoides were identified as potential As accumulators.

Selenium (Se) is a non-metallic element, which has the capability to increase the antioxidative capacity and stress tolerance of plants to heavy metals. Plants vary considerably in their physiological response to Se. The reported research investigated the effects of Se on arsenic (As) uptake by As hyperaccumulator Pteris vittata L. and determined possible mechanisms of interaction. Pteris vittata plants were exposed hydroponically to 0, 150 or 300 l Mo f Na 2HAsO4 in the presence of 0, 5 or 10 l Mo f Na 2SeO4 for 5 or 10 d. Application of 5 lM Se enhanced As concentration by P. vittata fronds by 7-45%. At 5 lM, Se acted as an antioxidant, inhibiting lipid peroxidation (reduced by 26-42% in the fronds) via increased levels of thiols and glutathione (increased by 24% in the fronds). The results suggest that Se is either an antioxi- dant or it activates plant protective mechanisms, thereby alleviating oxidative stress and improving arsenic uptake in P. vittata. Published by Elsevier Ltd.

Phytoremediation is a traditional technique that uses vegetation to remediate contaminants from water, soil and sediments. This is a solar-driven, aesthetically pleasing, and cost effective technology. In a former published article, Kalimeris integrifolia Turcz. ex DC. indicated some basic properties of hyperaccumulators for cadmium (Cd). In this study, concentration gradient experiment and sample-analyzing experiments were used to assess whether this plant is a Cd-hyperaccumulator. The results showed the Cd enrichment factor (concentration in plant/soil) and Cd translocation factor (concentration in shoot/root) of K. integrifolia was basically >1 in concentration gradient experiment. Shoot biomass was not reduced significantly (p

Phytoremediation, an emerging, plant-based technology for the removal of toxic contaminants from soil and water, has been receiving increased attention. The prerequisite for successful phytoremediation is the existence of hyperaccumulator plants. Designed to search for new arsenic (As) hyperaccumulators, an experiment was conducted under greenhouse conditions in a completely randomized design with four replications. This experiment identified Pteris biaurita L., P. quadriaurita Retz and P. ryukyuensis Tagawa as new hyperaccumulators of As and re-confirmed Pteris cretica as a hyperaccumulator. The average As concentration ranged from 1770 to 3650 mg kg(-1) DW in the fronds and 182 to 507 mg kg(-1) DW in the roots of P. cretica, P. biaurita, P. quadriaurita and P. ryukyuensis after having been grown in 100 mg As kg(-1) soil. There was a greater percentage of As(III) as compared to As (V) in the fronds of these plants. Based on our study, P. ryukyuensis is the most promising candidate to phytoremediate As contaminated soils compared to the other three species. The nutrient requirements or distributions within the Pteris species were altered distinctly when the plants were exposed to As.

There has been an interest in using hyperaccumulating plants for the removal of heavy metals and metalloids. High selenium (Se) concentrations in the environment are detrimental to animals, humans, and sustainable agriculture, yet selenium is also an essential nutrient for humans. This experiment was conducted to screen fern plants for their potential to accumulate selenium. Eleven fern species, Pteris vittata, P. quadriaurita, P. dentata, P. ensiformis, P. cretica, Dryopteris erythrosora, Didymochlaena truncatula, Adiantum hispidulum, Actiniopteris radiata, Davallia griffithiana, and Cyrtomium fulcatum, were grown under hydroponic conditions for one week at 20 mg L(-1) selenate or selenite. Root Se concentrations reached 245-731 and 516-1082 mg kg(-1) when treated with selenate and selenite, respectively. The corresponding numbers in the fronds were 153-745 and 74-1,028 mg kg(-1) with no visible toxicity symptoms. Only three fern species were able to accumulate more Se in the fronds than the roots, which were D. griffithiana when treated with selenate, P. vittata when treated with selenite, and A. radiata regardless of the forms of Se. A. radiata was the best species overall for Se accumulation. More research is needed to further determine the potential of the fern species identified in this study for phytoremediation of the Se contaminated soils and water.

Plant species capable of hyper-accumulating heavy metals are of considerable interest for phytoremediation, and differ in their ability to accumulate metals from the environment. This work aims to examine (i) arsenic accumulation in three fern species [Chinese brake fern (Pteris vittata L.), slender brake fern (Pteris ensiformis Burm. f.), and Boston fern (Nephrolepis exaltata L.)], which were exposed to 0, 150, or 300 muM of arsenic (Na(2)HAsO(4).7H(2)O), and (ii) the role of anti-oxidative metabolism in arsenic tolerance in these fern species. Arsenic accumulation increased with an increase in arsenic concentration in the growth medium, the most being found in P. vittata fronds showing no toxicity symptoms. In addition, accumulation was highest in the fronds, followed by the rhizome, and finally the roots, in all three fern species. Thiobarbituric acid-reacting substances, indicators of stress in plants, were found to be lowest in P. vittata, which corresponds with its observed tolerance to arsenic. All three ferns responded differentially to arsenic exposure in terms of anti-oxidative defence. Higher levels of superoxide dismutase, catalase, and ascorbate peroxidase were observed in P. vittata than in P. ensiformis and N. exaltata, showing their active involvement in the arsenic detoxification mechanism. However, no significant increase was observed in either guaiacol peroxides or glutathione reductase in arsenic-treated P. vittata. Higher activity of anti-oxidative enzymes and lower thiobarbituric acid-reacting substances in arsenic-treated P. vittata correspond with its arsenic hyper-accumulation and no symptoms of toxicity.

The National Botanical Research Institute (NBRI), Lucknow — established in 1953 under the Council of Scientific & Industrial Research (CSIR) — is one of the premier plant based research organization in India. Formerly known as National Botanic Garden the NBRI was renamed in 1978 in the present form. It was the late Professor K. N. Kaul, the founder Director of the Institute, who created the Division of Cryptogamic Botany for the study of lower group of plants including Pteridophytes. Professor Bala Krishnan Nayar, the then Head of this Division, got established an independent, well-equipped laboratory for the study of Indian pteridophytes. Under the patronage of Prof. Kaul, extensive floristic surveys of all regions of India were initiated for building up a pteridophyte herbarium besides collection of material for laboratory studies and for cultivation in a newly established Fernery. The laboratory was devoted to the study of morphology including stelar and developmental morphology of sporophytes of Indian pteridophytes and morphology of the gametophytic generation, the two fields in which Prof. Nayar was keenly interested. Meanwhile, different workers initiated studies on other cryptogams, study of Algae under Dr. P. N. Srivastava, Fungi under Mr. R. N. Ghosh, Bryophytes under Dr. K. P. Srivastava and Lichens under Dr. Ajai Singh. Each of these disciplines got separated in later years as independent Sections, as they are today.

The study presents a detailed observation and analysis of karyotype and comparison of the morphological characteristics of the six distantly located populations of Isoetes coromandelina L. f. It has been observed that the plants of I. coromandelina are distributed throughout India and most of them are triploid except the sporadic occurrence of a few tetraploid and hexaploid cytotypes interspersed amongst them. A detailed karyotype analyses of diploid, triploid and tetraploid cytotypes indicate that all the cytotypes of northern India might have originated from the same common stock of the Coromandal coast plants and have later on migrated to different parts of the country.